> Here's the nub of my question. In a typical synth architecture there are
> very many parameters which take values 0..127. If I had a function
>
> int_subrange_encoder: int -> int -> param_value -> bytestring
>
> which took the bounds of a subrange and generated an encoder function for
> values of that subrange, and then in a voice-architecture description I
> had a list of very many records each of which contained an entry
>
> int_subrange_encoder 0 127
>
> would I suddenly have six million little closures, or would the compiler
> do common-subexpression elimination on them ?
As of now, the compiler doesn't do any common subexpression
elimination. Notice that CSE over function applications is hard,
because the compiler must make sure that the function has no side-effects.
E.g. assume your function int_subrange_encoder prints something after
receiving its first two arguments:
let int_subrange_encoder lo hi =
print_string "subrange_encoder was here!";
fun param -> ...
Then, CSE would be incorrect.
An easy thing to do is to let-bind the partial applications that
occur frequently:
let int_encoder = int_subrange_encoder 0 127
and then use "int_encoder" instead of "int_subrange_encoder 0 127"
in your descriptions.
Hope this helps,
- Xavier Leroy